Prior art in the area of solar collection is replete with examples of the use of folded reflective optical systems. Beam's U.S. Patent No. 3,988,166 is typical and represents the closest art found in this area. Levi-Setti's U.S. Patent No. 3,899,672 reveals an optical collection apparatus which is non-imaging; that is, no image of the energy source is formed at the exit aperture of the structure. Levi-Setti also sets out the two inherent requirements of effective solar collectors: (1) that they effectively concentrate energy from a larger area into a higher level of energy over a smaller area, and (2) that the structure be able to accept energy from the solar source in spite of diurnal and seasonal changes in the relative positions of source and collector. He also points out that the two requirements are generally in conflict, one with the other, in that the more effective the energy concentration is, the more difficult the tracking problem becomes. Levi-Setti points out that as the acceptance angle of the optical structure decreases (which is generally accompanied by an increased concentration factor), the time during which effective concentration will occur during a given day becomes shorter and more tracking is required for an effective system, or, as the concentration factor increases, there is a necessity generated for more diversely directed collectors operated in concert. In the latter case, much of the collector capacity goes unused during the available daylight period because of lack of illumination at the output apertures of the majority of the units. This means that the utilization of capital investment is relatively poor in those systems which depend upon multiple collectors in lieu of a single unit plus tracking mechanisms unless there exists a good tradeoff between the cost of the extra collectors and the cost of the tracking mechanism for a single unit.